The Sun’s nearest neighbor, Alpha Centauri, is actually a triple-star system —three stars bound together by gravity.

Alpha Centauri A and B are two bright, closely orbiting stars with a distant, dim companion, Proxima Centauri.

The binary appears to the unaided eye as a single star, the third brightest in the night sky, but it lies 4.37 light years from the Sun — Proxima Centauri claims the honor of being our true nearest neighbor at only 4.24 light years away.

It’s difficult to conceptualize such vast distances, but a popular analogy sets the Sun at the size of a grapefruit. If you wanted to get from your grapefruit-sized Sun to a grapefruit-sized Alpha Centauri system, you would have to travel about 2,500 miles, which is about the distance from coast to coast on the continental United States. And that’s just to the Sun’s closest neighbor!

So to escape global warming our only chance is to reach Alpha Centauri or beyond, at least 4 light years away, with a lot of material, food and people to build a colony. Of course clever scientists can make this come true...